Objective: This study aimed to evaluate the relationship between the components of the objective grading system developed by the American Board of Orthodontics (ABO) and smile esthetics in Class I extraction vs non-extraction cases.
Methods: A total of 40 extraoral smile images of orthodontically treated (20 extraction and 20 non-extraction) cases in the age group of 13-30 years and Class I skeletal malocclusion with an average mandibular plane angle were selected. Smile images were rated only by the orthodontist, and this panel included 12 members.